Process of producing potassium sulfate.



o" i rum ifi l rl .lllri.

G-EUEGE MORGAN, fil TOLEDO, GEM

fate; and l do hereby declare the following i to be e full, clear andexact, description of the invention, such as Will enable others 1oslrilled iii the are lo which it sppertziins to make and. use the some.

My invention relates to processes of pro duciiig potassium sulfate fromuluuite. lln the processes heretofore used is the produci; lion. orpouissiuiu sulfate from alurute, suli'r'ur (llGXHi gases and othervapors are pro duced Wlucii cause grout injury to regimsic-oi inprocesses embodying my iriveiimor the uluiiiie may be roasted or otemperature 20 suuiciens to cause the conversion or slunite intoWriter-soluble potassium sulfate which may he subsequently leached fromthe roast and the some time rendering all she other in dieuts of tieziluiiite and compounds ic 5 iiorrried, insoluble. Also, in llZLQPlOCQSSES embodying my invention, the sulfur (llOXlCl is iulieii up toform s sulfate compound thereby preventing any escape or the sulfurdioiud which otherwise would greatly iujure vegetation surrounding theplum in which processes for .l'ormuig potassium sulfate il'roiiialuriice is conducted.

in the process embodying my invention aluiiite is roasted iii a suitable:r'urnace in the presence of calcium oxid or calcium hydrate as atemperature Within certain limits and ior u period of time which willbesuliicieiii', to cuuse complete re octioii While the mixture isbeingroasted.

in the conduct of the process, alunitc is ground and is then mixed Withcalcium oxid or hydrate of lime in the proportion of about one ofcalcium hydrate to liour of ulunite.

This proportion may be varied according to the quantity of aluminum inthe alunite with is to be rendered insoluble; also, ii calcium oXid isused in place oi the calcium iydrute the ratio of the ingredients willbe The mixture is llieu placed. in u sure ble furnace, preferably in eruler-y :luruuce, the heat being directed inlio the discharging end ofthe furnace. The lzemperclure of the mixture Within the furnace israised to 15209" lolliziiig vets and is lilies. sir" Specificatiw oflimiters 3 Pureiii'ed our, 235 'lfdildi i lpplics'bion filed June 7,1915. serial No. 32,598.

A V I.

to 1800 F. end the this point uiicil the may be determined by scaly inthe processes involving he use my ra'lure is im enlzion the teuipcraiureheretofore required to make the aluminum insoluble and the potassiumsulfate soluble, may be greatly reduced.

After roaseiug, the roastedriiixlure is placed in leaching vols, Whilethe roasted mixture is still hot. W is H1811 direcled onto the roastedprod l- 7 F vats. The mixture is use of the live steer to take up asmuch sulfate as possible" 'i e ii ii oil and directed into size 11 i ll;Where if is again agitoled as before, lire Water taking up an additionalamount of lhe soluble potassium sulfate. This process is repeated untilthe solution becomes concentrated at about 200 ll T e sol directed intocryslallizicg allowed to stand and cool. here be cooled by artificial mein order o0 hasten the crystzmother liquor is their draw vat. in whichis located the ro which has been leached "rho u ll 7 the solution isdirected Fro u vet wherein the roasted product has been leached lo lessextent, that is, to the one which contains the next lesser'amount ofpotassium sulfate still uiidissolved. The solution is then cooduc'iiedthrough each of the falls succession iii. mariner, until ii; is directedupon the product which has just come "from the rtuistiiig :lurmice andhas not yet been leached.

The potassium crystals are then removed from the cryslellizing volts andcosy be dried and grounder otherwise treated us may be desired.

Having thus described my invention, Who-it 1 claim as new, and desire tosecure by lliel ters Potent, is,

l. 'llie process of 15 siuiu sulfate from aluminum insoluble of sulfurdior'd the alunite lire "rill leaching the roast, concentrating theleach and removing the potassium sulfate from the leach.

2. The process of forming potassium sul- 5 fate from alunite andrendering the alumi- Gopies of this patent may be obtained for fivecents each, by addressing the Commisalunite in the presence of calciumoxid at :1 temperature of about 1200 to 1800 F., leaching the roast andremoving the poms 1o slum sulfate from the leach.

In testimony whereof, I have hereunto signed my name.

GEORGE S. MORGAN sioner of Patents.

Washington, C.

